Shader "Custom/GrayShader"
{
	Properties
	{
      _MainTex ("Sprite Texture",2D) = "white"{}
      _Alpha ("Alpha",Range(0,1)) = 1
	}
		SubShader{
		  Tags{ "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" }
		  Blend SrcAlpha OneMinusSrcAlpha
		  Pass{

		  CGPROGRAM
#pragma vertex vert
#pragma fragment frag

#include "UnityCG.cginc"

		  sampler2D _MainTex;
	  float _Alpha;

	  struct v2f {
		  float4  pos : SV_POSITION;
		  float2  uv : TEXCOORD0;
	  };

	  float4 _MainTex_ST;

	  v2f vert(appdata_base v)
	  {
		  v2f o;
		  o.pos = UnityObjectToClipPos(v.vertex);
		  o.uv = TRANSFORM_TEX(v.texcoord, _MainTex);
		  return o;
	  }

	  half4 frag(v2f i) : COLOR
	  {
		  half4 texcol = tex2D(_MainTex, i.uv) * _Alpha;
		  texcol.rgb = dot(texcol.rgb, float3(0.3, 0.59, 0.11)); 
		  return texcol;
	  }
		  ENDCG

	  }
	  }
	Fallback "VertexLit"
}